Current injection devices are generally syringe-type devices, i.e., with a plunger which is moved inside a cylinder and expels the content through one end, where the needle for injecting the liquid into the patient can be connected, or it can be connected to systems previously implanted in the patient, such as catheters.
The injection flow rate is controlled by the speed of movement of the plunger, and such speed is controlled by trained and experienced healthcare personnel. Excessive flow rate can cause adverse effects in the patient such as broken veins, extravasations, etc. The same occurs with an excessive outlet pressure.
With syringe-type injection devices, injectable products must be administered by healthcare professionals except in the case of some small-volume intramuscular injections, such as some vaccines, or in the case of diabetics self-injecting insulin.
The presence of a healthcare professional is also necessary when injection devices in which there may be backflow of biological fluids, or a return of these fluids through the needle or system implanted in the patient, especially blood in the case of intravenous injections, are used.
Furthermore, the use of syringe-type injection devices generally involves the use of both hands, one for holding the cylinder or body and the other for moving the plunger, and this also makes the presence of a healthcare professional necessary to prevent unsuitable movements of the syringe which may hurt the patient.
Given the scarcity and the cost of healthcare professionals, there is a need for injection devices which can be used risk-free by non-specialized personnel.
The use of preloaded injection devices for facilitating the administration of injectable products to patients is well known. Different proposals are known in this sense, and in relation to ampoule-type proposals, those described in patents U.S. Pat. Nos. 4,475,906, 6,120,478, WO 93/09826, EP 0 077 779 and DE 3106382 can be cited. However, other than in exceptional cases, the preloaded injection devices known by the applicant must be used by healthcare professionals.
A similar drawback arises in the control of dosing products requiring delicate handling, such as corrosives or reagents in research laboratories and in other industrial sectors.
The present invention aims to solve these drawbacks.